【摘要】 背景:腰椎退变滑脱以上一椎体相对下一椎体向前滑移为典型特征,是中老年常见的脊柱疾病。这种椎体间滑移使椎管形态发生明显的改变和畸形;鲜有研究报道影响腰椎退变滑脱椎管狭窄的解剖因素,且在手术治疗时是否应该复位滑脱节段及恢复椎体间高度也仍然存在争议。目的:探索腰椎退变滑脱生理载荷下滑脱节段椎管容积的变化及其相关解剖因素。方法:纳入15例无症状志愿者为正常组,年龄(55±7)岁;15例L4滑脱患者为试验组,年龄(54±6)岁。将双X射线透视影像系统和螺旋CT检查相结合,从受试者腰椎薄层CT获取腰椎三维重建模型,匹配到双X射线透视影像系统捕获的不同活动体位时(平卧、站立、前屈位和后伸位)腰椎X射线图像上,重现生理载荷下腰椎椎体间三维运动状态。观测不同姿势下椎管容积变化和可能影响椎管容积变化的解剖参数(椎间盘高度、椎管横截面积、椎管左右直径、椎管前后直径、滑脱程度、姿势和间盘角度)。结果与结论:正常组和试验组的椎管容积在平卧位和前屈位时均大于站立和后伸位,且试验组椎管容积在所有4个姿势下均明显小于正常组(P<0.05)。Pearson相关分析表明,滑脱节段L4-5椎管容积与L4-5椎间盘后缘高度(γb=0.80)显著相关,与滑脱程度(γb=-0.61)高度相关,与L4-5椎间盘前缘高度(γb=0.28)和间盘角度(γb=-0.24)弱相关。提示腰椎退变滑脱患者椎管容积受多重因素影响,平卧位和前屈位时滑脱节段容积增大有助于解释在这些姿势下患者临床症状缓解。复位滑脱的椎体、减少椎间角度、椎间撑开和减压都能有效增加滑脱患者的椎管容积,缓解临床症状。更多还原

【Abstract】 BACKGROUND: Lumbar degenerative spondylolisthesis, typically characterized by the forward slippage of the superior vertebra of a lumbar motion segment, is a common spinal pathological condition in elderly individuals. Significant deformation and volume changes of the spinal canal can occur because of the vertebral slippage, but few data have been reported on these anatomic variations in lumbar degenerative spondylolisthesis patients. Whether to restore normal anatomy, such as reduction of the slippage and restoration of disc height, is still not clear in surgery. OBJECTIVE: To observe the volume change of the spine canal and anatomic factors affecting the spine canal volume in lumbar degenerative spondylolisthesis patients. METHODS: A total of 15 asymptomatic volunteers(normal group) at the age of 55±7 years and 15 patients with L4 spondylolisthesis(trial group) at the age of 54±6 years were recruited. Dual X-ray imaging system was combined with spiral CT. Lumbar three-dimensional reconstruction models were obtained from lumbarthin-section CT of subjects. In vivo lumbar vertebral motion during functional postures(supine, standing, flexion and extension) was observed using a dual fluoroscopic imaging technique. The volume of the spine canal was measured at each functional posture. Various anatomic parameters(disc height, cross-sectional area of the canal, left-right diameter of the canal, anterior-posterior diameter of the canal, slippage, posture, and intervertebral disc angle) that may potentially affect the canal volume were also measured. RESULTS AND CONCLUSION: Spine canal volume was larger at supine and flexion postures than at stand and extension postures in both the normal and trial groups. Spine canal volume in the trial group was significantly lower than that in the normal group under all the four postures(P < 0.05). Pearson correlation analysis showed that L4-5 spine canal volume was strongly correlated with the L4-5 posterior disc height(γb = 0.80), correlated with the slippage percentage(γb =-0.61), and weakly associated with the L4-5 anterior disc height(γb = 0.28) and the disc angle(γb =-0.24). Above data indicated that the volume of spine canal is affected by multiple factors in patients with lumbar degenerative spondylolisthesis. Increased spine canal volume at supine and flexion positions may explain the clinical observations of relief of symptoms at these postures in lumbar degenerative spondylolisthesis patients. The reduction of slipped vertebral body, decrease of disc angle, intervertebral distraction, as well as decompression could be effective to increase the canal volume and to relieve clinical symptoms.更多还原